Supporting spindle for centrifugal machines



M. LEITCH.

SUPPORTING SPINDLE FOR CENTRIFUGAL MACHINES. APPLICATION FILED NOV. 1h 1919.

1,409,958, 2 Patented Mar. 21, 1922.

2 SHEETS-SHEET I.

N N N d I N x;

9; w 2 w L M. LEITCH. I SUPPORTING SPINDLE FOR CENTRIFUGAL MACHINES.

APPLICATION FILED NOV. 11, I919.

Patented Mar. 21, 1922.

UNITED STATES PATENT. OFFICE...

MEREDITH LEITCH, OF POUGHKE-EPSIE, NEW YORK. vASSIGNDR TO DE LAVAL SEPARATOR COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

SUPPORTING SPINDLE FOR CENTRIFUGAL MACHINES. 7

Specification of Letters Patent.

Patentedltlar. 2.1, 1922.

Application filed November 11, 1919. Serial No. 337,282.

To all whom it may concern Be it known that I, Mnnnorrrr Lnlrcri, a citizen of the United States, residing at Poughkeepsie, county of Dutchess, and State of New York, have invented a new and useful Improvement in Supporting Spindles for Centrifugallilachines, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, which form a part of this specification.

My invention relates to centrifugalizing machines and particularly to thespindles of such machines.

In the larger sizes of centrifugal separators, etc., the spindle is generally made in two pieces. The lower piece runs in two bearings and between them carries, in steam driven machines, a steam wheel, and in rope, belt or worm and wheel driven machines, a pulley or worm. The upper piece, com monly called'the bowl spindle, has its lower end in a socket on the top of the lower piece. carries the centrifugal bowl on its upper end and is steadied by a bearing as high as possible under the bowl. When the bowl is not in perfect balance it causes a strong Side thrust at the top of the spindle which, acting as a lever of the first class with the upper steadying bearing as a fulcrum, throws the top of the lower spindle sideways. With a reasonable overall height of machine it is impossible to make the part of the bowl spindle below the steadying bearing and above the socket on the lower spindle as long, relative to the partbetween the steadying bearing and the bowl, as is desirable. The side pressure at the socket is, therefore, very great and the. lower spindle, acting as a lever of the second class with its lower bearing as a fulcrum, presses against its upper bearing with still greater force. These heavy pressures cause rapid wear ofall bear ings.

The object of my invention is to providea spindle wherein lever relations will be such that the bearing pressures will be greatly rc duced and yetretain the advantages due to a two-piece spindle.

In the accompanying drawings, which illustrate a preferred embodiment of my invention:

Fig. 1 is an elevation of one of my spindles for a steam driven machine with the centrifugal bowl and the bearings in place.

Fig. 2 is a. diagram illustrating the present lever construction and bearingpressures of a well known centrifugal separator mounted on a typical spindle of the prior art when the side thrust of the bowl is one hundred pounds. 7 Y

Fig. 3 is a similar diagram illustrating the lever proportions and bearing pressures for the same machine mounted on niy-improved spindle when the side thrust of the bowl is the same. s

Fig. 4: is a vertical sectional view of the machine showing the details of the bearings and supports Referring first to the constructionshown in Figure'l: I

The centrifugal bowl 9 is carried on and driven by a bowl (or upper) spindle h, which is steadied at the top" by a top yieldable or cushioned bearing 2' and at the bottom by the upper bushing j. The top or steadying bearing should be as high as possible on the bowl spindle and as near as possible to the bowl. The reduced lower end of the bowl spindle it enters a socket Z in the upper end of a lower spindle is. This socket is formed in an enlarged part of the lower spindle around which the hub of a steam wheel m is clamped. The lower end of the lower spindle turns in a bottom bushing n and is supported by a thrust bearing consisting of a steel point 0 resting on tread wheels 3) running on a horizontal shaft-carried in a step 1 screw 7 The bowl spindle. carries above the upper bushing j a pair ofworms s for driving a speed indicator and governor not shown.

In order that the advantages of this spindle'may be clearly apprehended, I have illustrated diagrammatically-in Figs. 2 and 3. the difference between a typical spindle of the prior art and my improved spindle.

Referring to Fig. 2: a is the center of gravityofthebowl and a side thrust of one hundred pounds is assumed "to be exertedagainst the spindle. e" is the center of the top bearing,.where a resistanceof 17 7 pounds must be exerted to hold the spindle. 1; is" the-point where the'bottom of the bowl spindle fits in a socket on the top of the lower spindle and exerts a side pressure of seventyseven pounds against the socket. At y" the lower spindle is guided by its upper bushing against which it presses with a force of 145 pounds and causes rapid'wear. At n the lower end of the lower spindle is guided by a bottom bushing against which it presses with a force of sixty-eight pounds. 0' is the thrust bearing that supports all revolving parts. J

a indicates the center of gravity of a bowl monnted' on one of my improved spindles. i is the center of the top bearing where the pressure is 148 pounds, a reduction of 16.5%. j" is the upper bushing where the pressure will be only forty-eight pounds or less than one-third of that with the old type of spindle. l is the point where the bottom end of the bowl spindle fits in a socket on the top oi. the. lower spindle. Here there is no side thrust. n is the bottom bushing that guides thelower end of the lower spindle and against which there isno side thrust. 0 is the thrust bearing.

It will thus be seen that I have succeeded in greatly reducing the bearing pressures in the case of the upper bearing and the top bushing,and have eliminated the side thrust in the case of the lower bushing and the socket of the lower spindle.

Having now fully described my invention, what I claim and. desire to protect by Letters Patent is: a

1. In a centrit'ugalizing machine, in co1nbination, a centrifugal how], a lower spindle, a bowl spindle mountedon the lower slpindle, a bearing; guiding the lower spinle, the upper end oi? the lower spindle being unsupported except by its engagement with the bowl spindle, a bearing independ ent of the bearing for the lower spindle and non-yielda-bly guiding the bowl spindle near its lower end, and a spring-supported bearing independent of the other bearings and. guiding the bowl spindle relatively near its top. a

2. In a centrifugal machine, in combination, a bowl, a lower supporting spindle and a bearing guiding it near its lower end, an

upper spindle supported by the lower spindleand supporting the bowl, and a plurality of bearings .for the upper spindle which are independent 01 each other and of any bearing for the lower spindle'and the up er only of which is spring-supported and w ich are so positioned as tojavoid substantial side thrust at the junction of the two spindles.

3. In a centritugalizingmachine, in c0mbination, a thrust bearing, a lower spindle turning therein and supported thereby, a bearing for the lower spindle near its lower end, an upper spindle, a sooketed connection between the two spindles, the upper end of the lower spindle being otherwise unsupported, and a pin ality of lHLlB'pOIHlODl) bearings each guiding solely the upper spindle, the lower bearing for theupper spindle being non-yieldable and the upper bearing for the upper spindle being yieldable, the two last named bearings being so positioned as to minimize side thrust against them and substantially eliminate side thrust against the lower bearing and at said socketed connection.

1. Driving mechanism forth-e bowl of a centrifugal machine comprising a two part spindle, astep bearing for the lower member of the spindle, a bearing sleeve for said member near the lower end, a bearing sleeve independent oi any bearing for the lower spindle member and guiding solely the upper spindle member above the upper end of the lower spindle member, a steadying' connection between the upper end of the lower spindle member and the lower end of the upper spindle member, and a steadyinp; bearing sleeve for the upper end of the upper spindle member independent of said bearing sleeve for its lower end.

5. A two part spindle for thebowl oi a centrifugal machine having a lower member and an upper member sumiorted thereby, a pin and socket connection between the two members, a step bearing for the lower member, a bearing sleeve for the lower member near the lower end thereof, two separate and independent bearing sleeves guiding solely the upper member of the spindle. the lower of the last two sleeves being entirely above the lower member of the spindle while the upper sleeve isjust below the bottom of the bowl, and means for driving the lower member of the spindle.

6. In a centrifugalmachine, in combination, a centrifugal bowl, a lower spindle, an upper bowl spindle, and three bearings; one bearing carrying the lower end of the lower spindle, a second bearing non-yieldably guiding solely the lower end of the bowl spindle, and a spring-supported third bearing independent ol. the second bearing and guiding the bowl spindle relatively near its top, the upper bowl spindle guiding the lower spindle whoseupper end is otherwise unsupported, whereby the bearing pressures at the upper and intermediate bearings are minimized and the side thrusts at the lower bearing and at thejoint between the spindles are substantially: eliminated.

In testimony of which invention, 1- have hereunto set my hand, at Poughkeepsie, N. Y., on this 7th day of November, 1919.

MEREDITH LEITCH.

. l .ullllllllll 

